Pandebonium 1 - 5 This is ugly. The one win was from a really strong start, I managed to out-mitosis the Pandemonium, and I deflagged an Arsenic early on that didn't get replaced until too late. Mitosis'ed Phoenixes are very very fragile.
Deck Death used against Time: 1 - 5 Outrushed. Bone Wall is OP. Death is OP.
Deck Death used against Aether: 5 - 2 Originally went 3-0, but decided to go to 5 because the games were close. Every heal counts against a deck like this.
Winged Toadfish + CC from Air: 0 - 3 Countered. Hard. 1 HP creatures do not take well to poison, Adrenaline'd or not. AI doesn't hesitate to poison the Ashes, so the reincarnated Phoenix's die next turn... again.
Deck Water used against Earth: 3 - 5 Against the AI, the games were close. If it were an actual person, I doubt I'd have gotten more than 1 win. CC is, apparently, this decks worst nightmare.
Deck Water used against Death: 3 - 0 Easy wins. Easily outdamaged, and without BW, Pandemonium just isn't as dangerous to creatures as resilient as Phoenixes.
Light/Aether duo: 0 - 3 1 Deflag versus 5 Dimensional Shields. Nothing else to say, really.
Deck Light used against Life: 5 - 1 Light's deck is strong, but not fast enough. None of the games I won were particularly close, even without drawing Heals a couple times.
Deck Light used against Fire: 5 - 1 At first glance, I figured this would be really hard, if not impossible, to beat before I decked out. Diamond Shield makes MP all but useless, but unupgraded Phoenix does just fine, if you hold Deflag till you can kill.
Discord Grabbow: 0 - 3 Discord is cruel. Eventually your quanta production overruns Discord scrambling, but by then its too late.
Deck Entropy used against Life: 1 - 5 Nasty. Between early Discord, upped Pandemonium, Maxwell's, and that oh-so-cruel Nymph, this is a no contest fight. My win came from a strong start where I managed to Rage Potion a Maxwell's and the Nymph early on, and Deflag a Discord which didn't get replaced at all.
Deck Entropy used against Death: 5 - 1 Close games. Saving Rage Potions for Maxwell's is really what made the difference between 5 - 1 and 1 - 5.
Busy day today, I didn't get as much testing done as I had hoped. Will continue tomorrow.
PUgons Earth Version: 1 - 0 I quit this one. AI doesn't play this deck even remotely well. DimShield the turn after I play a single MP, PU'ing my Phoenixes when it has a dragon...
Earth Firestall: 1 - 0 AI doesn't play Firestalls correctly. Just gonna skip this one too, bolting my Phoenixes isn't how you win with a Firestall.
Deck Earth used against Aether: 0 - 3 I thought this was gonna be a walkover. Nope, apparently this deck is very sturdy, and Nightmare serves to slow you down just enough that you get outrushed.
Deck Earth used against Darkness: 5 - 3 Games were decided by how early the Owl's Eye came out, if I had Deflag (if it came out early) and if the Owl's Eye got replaced quickly.
Deck Air used against Entropy: 0 - 3 Countered. Hard. With so much CC in one deck, its basically impossible to hope that he won't draw some of it early.
Deck Air used against Time: 0 - 3 Eagle's Eye + Bone Wall + reviving Phoenixes = unbreakable Bone Wall. A win might be possible if you managed to Deflag the Eagle's Eye without getting it replaced, but I wouldn't count on it.
Overall assessment: Best against Water and Light. Bad against CC. Winning or losing is usually clear, only a few decks result in really close matches.